What determines a specific trait?
DNA determines a specific trait.
The expression of a specific trait in an individual (such as hair color) is determined by two factors, one from each parent. These factors are represented with an uppercase letter for a dominant factor and a lowercase letter for a recessive factor. The combination of these factors determines how that trait will be expressed in an individual.
In genetics, a trait is considered dominant when it determines a phenotype over a recessive trait. For example, AA is crossed with AA to make Aa, Aa, Aa, and Aa. If "A" is the dominant trait and "a" is the recessive trait, then since this cross produces heterozygous progeny, they will all show the dominant phenotype. A dominant trait is just how it sounds, it dominates over recessive traits when they are both present.
What is a person who has one recessive allele for a trait and one dominant allele for the same trait?
Dominant inheritance is dominant and determines the trait, while Recessive inheritance is hidden by the dominant trait. A recessive trait is exhibited only if both recessive genes are present. Organisms that carry recessive genes but do not exhibit theme are called carriers. If an organism is heterozygous for a dominant trait, each of its offspring has a 50 percent chance of inheriting the trait.
DNA (deoxyribonucleic acid) is the chemical which contains the information which determines heredity. Every inherited trait is the result of some particular DNA sequence. There are four types of DNA base chemicals, which can be connected in any sequence, and the specific sequence, known as a gene, will result in specific traits. Genetics has a language, written with only 4 letters.